Spiro's work was initially intended to serve foreign residents in Egypt, foreign officials in the service of the Egyptian government, and winter tourists. Foreign residents and foreign officials are far fewer than they used to be; so are the leisurely tourists who are likely to take trouble to learn the local idiom. Yet the number of potential users of this dictionary-especially of those who are likely to make sustained and serious use of it-has increased rather than diminished. Businessmen and diplomats will find obvious advantages in it. Specialists in various branches of linguistics will want to exploit it. Folklorists will use it as a key to a vast treasure-house whose anthropological, sociological, and literary value has too long been ignored. And even the general student of Arab thought and Arab affairs will have to reckon with the fact that the colloquial has for some time now been part and parcel of elitist writing. Many significant plays are entirely in the colloquial; the dialogue of innumerable novels and short stories is in the colloquial; some good poetry is being writen in the colloquial. Even writers resolutely opposed to making the colloquial into ''the language of literature'' such as Najib Mahfuz borrow from it purely local words such as Wikala (a low-class in including accommodation for pack-animals) the meaning of wich is unknown even to Arabs from other regions, can not be deduced from the classical root, and does not appear to have been recorded in any dictionary other than Spiro's.

A very welcome feature of Spiro's dictionary is that it is not content with literal translations but pays considerable attention to idiomatic usages.